U.S. patent application number 15/149602 was filed with the patent office on 2017-01-26 for footwear including a textile upper.
The applicant listed for this patent is Under Armour, Inc.. Invention is credited to David Dombrow, Kevin P. Fallon, Thomas White.
Application Number | 20170020229 15/149602 |
Document ID | / |
Family ID | 57222254 |
Filed Date | 2017-01-26 |
United States Patent
Application |
20170020229 |
Kind Code |
A1 |
Dombrow; David ; et
al. |
January 26, 2017 |
FOOTWEAR INCLUDING A TEXTILE UPPER
Abstract
An article of footwear includes a sole structure and an upper
attached to the sole structure. The upper is formed from a textile
including interlocked strands oriented in a predetermined
configuration. The strands include one or more inelastic strands
operable to provide stretch and/or recovery properties to the
upper.
Inventors: |
Dombrow; David; (Baltimore,
MD) ; Fallon; Kevin P.; (Portland, OR) ;
White; Thomas; (Baltimore, MD) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Under Armour, Inc. |
Baltimore |
MD |
US |
|
|
Family ID: |
57222254 |
Appl. No.: |
15/149602 |
Filed: |
May 9, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62158709 |
May 8, 2015 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A43B 5/06 20130101; D04B
1/123 20130101; A43B 1/04 20130101; A43B 23/02 20130101; D04B 1/22
20130101; D10B 2501/043 20130101; A43B 23/0205 20130101; A43B
23/0245 20130101; A43B 23/028 20130101; A43B 7/085 20130101; A43C
1/04 20130101; A43C 5/00 20130101; D04B 1/16 20130101; A43B 23/088
20130101; A43B 23/0275 20130101; A43C 1/00 20130101; A43B 23/0255
20130101; A43B 23/0235 20130101; A43B 23/086 20130101; D10B
2401/041 20130101; D10B 2403/02 20130101 |
International
Class: |
A43B 23/02 20060101
A43B023/02; A43C 1/04 20060101 A43C001/04; A43B 23/04 20060101
A43B023/04; A43B 7/08 20060101 A43B007/08; A43B 5/06 20060101
A43B005/06 |
Claims
1. An article of footwear including a foot cavity, the article of
footwear comprising: a sole structure; and an upper coupled to the
sole structure, the upper defining a forward section, a rearward
section, and an intermediate section disposed between the forward
section and the rearward section, the upper comprising a knit
structure with strands oriented in courses and wales, the strands
including a plurality of bicomponent strands, each bicomponent
strand of the plurality of bicomponent strands comprising a first
component polymer integrally formed with a second component
polymer, wherein each bicomponent strand is adapted to enable
stretch and recovery within the knit structure.
2. The article of footwear according to claim 1, wherein the first
component polymer and the second component polymer are disposed in
a sheath-core relationship such that the first component polymer is
a sheath that surrounds a core formed by the second component
polymer.
3. The article of footwear according to claim 1, wherein the first
component polymer and the second component polymer are oriented in
side-by-side relationship.
4. The article of footwear according to claim 3, wherein each
bicomponent strand is an eccentric strand, with the first component
polymer and second component polymer being oriented asymmetrically
about an axis.
5. The article of footwear according to claim 1, wherein each
bicomponent strand is coiled along a length of the bicomponent
strand.
6. The article of footwear according to claim 1, wherein the
plurality of bicomponent strands form approximately 40% to 60% of
the knit structure courses.
7. The article of footwear according to claim 1, wherein the knit
structure excludes elastomeric strands.
8. The article of footwear according to claim 1, wherein the knit
structure excludes elastane.
9. The article of footwear according to claim 1, wherein the first
component polymer possesses one or more properties that differ from
the properties of the second component polymer.
10. The article of footwear according to claim 9, wherein the first
component polymer possesses a first rate of shrinkage and the
second component polymer possesses a second rate of shrinkage, the
first rate of shrinkage differing from the second rate of
shrinkage.
11. The article of footwear according to claim 1, wherein each
bicomponent strand of the plurality of bicomponent strands is a
polyester bicomponent strand comprising a first component polymer
of poly(trimethylene terephthalate) and a second component polymer
selected from the group consisting of poly(ethylene terephthalate),
poly(tetramethylene terephthalate), and combinations thereof.
12. The article of footwear according the claim 1, wherein: the
upper comprises: a heel section including a heel cup configured to
align with the calcaneus area of a human foot, a lateral quarter
section disposed forward the heel section and oriented on a lateral
side of the article of footwear, a medial quarter section disposed
forward the heel section and oriented on a medial side of the
article of footwear, a vamp section disposed forward the lateral
and medial quarter sections, and a toe cage section disposed
forward the vamp section; and one or more of the heel, lateral
quarter, medial quarter, vamp, and toe cage sections comprises the
knit structure including the plurality of bicomponent strands.
13. The article of footwear according to claim 12, wherein each of
the heel, lateral quarter, medial quarter, vamp, and toe cage
sections comprises the knit structure including the plurality of
bicomponent strands.
14. The article of footwear according to claim 13, wherein the
upper possesses a unitary construction such that each section
shares a common strand with adjacent sections.
15. The article of footwear according to claim 14, wherein each
section is integral with adjacent sections.
16. The article of footwear according to claim 1, wherein the knit
structure further comprises a plurality of non-bicomponent strands
selected from the group consisting of inelastic strands, heat
sensitive strands, and thermally conductive strands.
17. The article of footwear according to claim 1, wherein the knit
construction further comprises a plurality of strands fused to
adjacent strands.
18. A method of forming an article of footwear, the method
comprising knitting a footwear structure including courses and
wales by inserting a bicomponent strand into selected courses
within the structure, wherein the bicomponent strand includes a
first component polymer integrally formed with a second component
polymer.
19. The method according to claim 18 further comprising inserting
fusible strands into selected courses within the structure.
20. The method according to claim 20 further comprising obtaining a
sole and coupling the sole to the footwear structure.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to Provisional
Application No. 62/158,709, filed 8 May 2015 and entitled "Footwear
Including a Textile Upper." The disclosure of the aforementioned
application is incorporated herein by reference in its
entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to an article of footwear and,
in particular, footwear including an upper with stretch
properties.
BACKGROUND
[0003] Articles of footwear typically include an upper and a sole
structure attached to the upper. When the upper is knitted, an
elastomeric strand may be added to provide the upper with stretch
and/or recovery properties. Adding elastomeric strands, however,
adds weight to the upper (and thus the footwear), as well as
increases water retention in the upper. Accordingly, it would be
desirable to provide stretch properties to portions of an upper
without utilizing elastomeric yarns.
SUMMARY OF THE INVENTION
[0004] An article of footwear includes a sole structure and an
upper attached to the sole structure. The upper is formed from a
textile including interlocked strands oriented in a predetermined
configuration. The strands include one or more inelastic strands
operable to provide stretch and/or recovery properties to the
upper.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] FIG. 1 is an exploded view of an article of footwear in
accordance with an embodiment of the invention (footwear configured
for a right foot).
[0006] FIG. 2A is side view in elevation of the article of footwear
shown in FIG. 1, showing the medial footwear side.
[0007] FIG. 2B is a side view in elevation of the article of
footwear shown in FIG. 1, showing the lateral footwear side.
[0008] FIG. 2C is a front perspective view of the article of
footwear of FIG. 1, showing the lateral footwear side.
[0009] FIG. 2D is a front perspective view of the article of
footwear shown in FIG. 1, showing the medial footwear side.
[0010] FIG. 2E is a rear perspective view of the article of
footwear shown in FIG. 1, showing the medial footwear side.
[0011] FIG. 3 is a side view in elevation of the article of
footwear shown in FIG. 1, showing the lateral footwear side and
further including a partial cut-out section.
[0012] FIG. 4 is a cross-sectional view of a bicomponent fiber in
accordance with an embodiment.
[0013] FIG. 5 is a schematic of an exemplary knit construction.
[0014] FIG. 6 is a front perspective view of an article of footwear
in accordance with an embodiment of the invention.
[0015] FIG. 7 is a graph illustrating dry times of knitted textile
including bicomponent fiber compared to knitted textile lacking
bicomponent fiber.
[0016] FIG. 8 is a flow chart disclosing a method of forming an
article of footwear.
[0017] Like reference numerals have been used to identify like
elements throughout this disclosure.
DETAILED DESCRIPTION
[0018] As described herein with reference to the example embodiment
of FIGS. 1-3, an article of footwear 100 includes an upper 105
coupled to a sole structure 110 and further including a heel
counter 115 and a fastening element or fastener 120 (e.g., a lace
or cord, which is shown in phantom). The article of footwear 100 is
an athletic shoe (e.g., a running shoe) defining a forefoot region
200A, a midfoot region 200B, and a hindfoot region 200C, as well as
a medial side 205A and a lateral side 205B. The forefoot region
200A generally aligns with the ball and toes of the foot, the
midfoot region 200B generally aligns with the arch and instep areas
of the foot, and the hindfoot region 200C generally aligns with the
heel and ankle areas of the foot. Additionally, the medial side
205A is oriented along the medial (big toe) side of the foot, while
the lateral side 205B is oriented along the lateral (little toe)
side of the foot.
[0019] The upper 105 includes and/or defines a plurality of
sections that cooperate to define the foot cavity. A heel section
210 includes heel cup configured to align with and cover the
calcaneus area of a human foot. A lateral quarter section 215,
disposed forward the heel section 210, is oriented on the lateral
shoe side 205B. Similarly, a medial quarter section 220, disposed
forward the heel section 210, is oriented on the medial shoe side
205A. A vamp section 225 is disposed forward the quarter sections
215, 225; moreover, a toe cage section 230 is disposed forward the
vamp section. The upper 105 may further include an instep cover
section 240 configured to align and span the instep area of the
foot as well as a planum section or footbed 300 (FIG. 3) that
engages the planum (bottom) of the foot.
[0020] With this configuration, the heel 210, lateral quarter 215,
medial quarter 220, vamp 225, toe cage 230 and planum 300 sections
cooperate to form a foot cavity 332 (FIG. 3) into which a human
foot is inserted by way of an access opening 235 formed
cooperatively by the heel 210, the lateral 215 and medial 220
quarters, and the instep cover 240.
[0021] Referring to FIG. 2C, the lateral quarter section 215
extends from the heel section 210 to the vamp section 225,
traveling upward from the planum section 300 such that the lateral
quarter spans the lateral side of the foot, proximate the hindfoot
and midfoot areas. The lateral quarter 215 may be formed integrally
with the heel section 210, the vamp section 225, and the planum
section 300. The lateral quarter 215 is adapted to receive a
fastener such as a shoe lace. In an embodiment, the lateral quarter
215 includes a plurality of looped sections 245A, 245B, 245C, 245D
disposed at the lateral quarter distal edge (upper edge). As
illustrated, the looped sections 245A-245D are linearly spaced,
being generally aligned in an array extending longitudinally along
the shoe 100. In this manner, each looped section 245A-245D is
configured to receive the fastener 120 (the shoe lace), movably
capturing the fastener therein. The looped sections 245A-245D,
moreover, cooperate with one or more elements disposed on the
instep cover 240 to engage the fastener 120 (shown in phantom) to
secure the shoe 100 to the foot of the wearer.
[0022] Referring to FIGS. 2D and 2E, the medial quarter 220 extends
from the heel 210 to the vamp 225, traveling upward from the planum
300 such that the medial quarter spans the medial side of the foot,
proximate the hindfoot and midfoot areas. The medial quarter 220
may be seamlessly and/or stitchlessly integrated with each of the
heel 210, vamp, and planum 300 sections of the upper 105.
[0023] The instep cover 240 is configured to span the dorsum
portion of the midfoot (i.e., the instep). The instep cover 240 may
be formed integrally (stitchlessly and/or seamlessly) with the
medial quarter section 220. As best seen in FIG. 3, the instep
cover 240 defines a forward edge 305 (oriented toward the vamp 225)
and a rearward edge 310 oriented generally parallel to the forward
edge. The instep cover 240 further defines distal edge 315 oriented
generally orthogonal to the forward and rearward edges. The instep
cover 240 generally spans the instep of the foot, extending from
the medial shoe side 205A to the lateral shoe side 205B, and
extending from the throat line 250 of the vamp 225 at its forward
edge 305 to the access opening 235 at its rearward edge 310. As
noted above, the access opening 235 is partially defined by the
rearward edge 310.
[0024] The instep cover 240 may include one or more narrow,
elongated openings or slots 260 operable to permit passage of the
fastener 120 therethrough. The instep cover 240 may also include
additional openings or windows 285 operable to improve airflow
into/out of the upper.
[0025] The forefoot region 200A of the upper 105 includes the vamp
section 225, which extends forward from the lateral 215 and medial
220 quarters, being formed integrally therewith. The vamp section
225 includes the throat line 250 within its proximal region and toe
cage 230 within its distal region, the toe cage being configured to
span the toes of the foot.
[0026] In an embodiment, the upper 105 (or one or more sections) is
a textile formed via knitting. Knitting is a process for
constructing fabric by interlocking a series of loops (bights) of
one or more strands organized in wales and courses. In general,
knitting includes warp knitting and weft knitting. In warp
knitting, a plurality of strands runs lengthwise in the fabric to
make all the loops.
[0027] In weft knitting, one continuous strand runs crosswise in
the fabric, making all of the loops in one course. Weft knitting
includes fabrics formed on both circular knitting and flat knitting
machines. With circular knitting machines, the fabric is produced
in the form of a tube, with the strands running continuously around
the fabric. With a flat knitting machine, the fabric is produced in
flat form, the threads alternating back and forth across the
fabric. In an embodiment, the upper 105 is formed via flat knitting
utilizing stitches including, but not limited to, a plain stitch; a
rib stitch, a purl stitch; a missed or float stitch (to produce a
float of yarn on the fabric's wrong side); and a tuck stitch (to
create an open space in the fabric). The resulting textile includes
an interior side (the technical back) and an exterior side (the
technical face), each layer being formed of the same or varying
strands and/or stitches. By way of example, the textile may be a
single knit/jersey fabric, a double knit/jersey fabric, and/or a
plated fabric (with yarns of different properties are disposed on
the face and back). In a specific embodiment, the upper textile is
a double knit fabric formed via a flat knitting process.
[0028] Utilizing knitting, the entire upper 105 (or selected
sections) may be configured as a unitary structure (i.e., it may
possess a unibody construction) to minimize the number of seams
utilized to form the shape of the upper. For example, the upper 105
may be formed as a one-piece template, each template portion being
integral with adjacent template portions. Accordingly, each section
210, 215, 220, 225, 230, 240, 300 of the upper 105 may include a
common strand interconnecting that section with adjacent sections
(i.e., the common strand spans both sections). In addition, the
connection between adjacent sections may be stitchless and
seamless. By stitchless and/or seamless, it is meant that adjacent
sections are continuous or integral with each other, including no
edges that require joining by stitches, tape, adhesive, welding
(fusing), etc.
[0029] The strands forming the knitted textile (and thus the upper
105) may be any natural or synthetic strands suitable for their
described purpose (i.e., to form a knit upper). The term "strand"
includes one or more filaments organized into a fiber and/or an
ordered assemblage of textile fibers having a high ratio of length
to diameter and normally used as a unit (e.g., slivers, roving,
single yarns, plies yarns, cords, braids, ropes, etc.). In a
preferred embodiment, a strand is a yarn, i.e., a continuous strand
of textile fibers, filaments, or material in a form suitable for
knitting, weaving, or otherwise intertwining to form a textile
fabric. A yarn may include a number of fibers twisted together
(spun yarn); a number of filaments laid together without twist (a
zero-twist yarn); a number of filaments laid together with a degree
of twist; and a single filament with or without twist (a
monofilament).
[0030] The strands may be heat sensitive strands such as flowable
(fusible) strands and softening strands. Flowable strands are
include polymers that possess a melting and/or glass transition
point at which the solid polymer liquefies, generating viscous flow
(i.e., becomes molten). In an embodiment, the melting and/or glass
transition point of the flowable polymer may be approximately
80.degree. C. to about 150.degree. C. (e.g., 85.degree. C.).
Examples of flowable strands include thermoplastic materials such
as polyurethanes (i.e., thermoplastic polyurethane or TPU),
ethylene vinyl acetates, polyamides (e.g., low melt nylons), and
polyesters (e.g., low melt polyester). Preferred examples of
melting strands include TPU and polyester. As a strand becomes
flowable, it surrounds adjacent strands. Upon cooling, the strands
form a rigid interconnected structure that strengthens the textile
and/or limits the movement of adjacent strands.
[0031] Softening strands are polymeric strands that possess a
softening point (the temperature at which a material softens beyond
some arbitrary softness). Many thermoplastic polymers do not have a
defined point that marks the transition from solid to fluid.
Instead, they become softer as temperature increases. The softening
point is measured via the Vicat method (ISO 306 and ASTM D 1525),
or via heat deflection test (HDT) (ISO 75 and ASTM D 648). In an
embodiment, the softening point of the strand is from approximately
60.degree. C. to approximately 90.degree. C. When softened, the
strands become tacky, adhering to adjacent stands. Once cooled,
movement of the textile strands is restricted (i.e., the textile at
that location stiffens).
[0032] One additional type of heat sensitive strand which may be
utilized is a thermosetting strand. Thermosetting strands are
generally flexible under ambient conditions, but become
irreversibly inflexible upon heating.
[0033] The strands may also include heat insensitive strands. Heat
insensitive strands are not sensitive to the processing
temperatures experienced by the upper (e.g., during formation
and/or use). Accordingly, heat insensitive strands possess a
softening, glass transition, or melting point value greater than
that of any softening or melting strands present in the textile
structure and/or greater than the temperature ranges specified
above.
[0034] The upper 105 further includes a strand formed of
non-elastomeric material, i.e., an inelastic strand. In
conventional uppers, elastic strands are utilized to provide a
textile upper with stretch and recovery properties. An elastic
strand is formed of elastomeric material (e.g., rubber or a
synthetic polymer having properties of rubber). Accordingly, an
elastic strand possesses the ability to stretch and recover by
virtue of its composition. A specific example of an elastomeric
material suitable for forming an elastic strand is an elastomeric
polyester-polyurethane copolymer such as elastane, which is a
manufactured fiber in which the fiber-forming substance is a long
chain synthetic polymer composed of at least 85% of segmented
polyurethane.
[0035] The degree to which fibers, yarn, or cord returns to its
original size and shape after deformation indicates how well a
fabric/textile recovers. Even when utilized, the upper does not
quickly recover to its original size and shape. Sagging will
develop within the upper over time, caused by the incomplete
recovery within the structure. An elastic strand such as elastane,
moreover, retains water, potentially creating wearer discomfort. In
addition, elastane must be braided onto an existing yarn or
completed covered by another fiber, increasing the weight of the
textile (i.e., it cannot be the sole component of a course within
the knit structure).
[0036] In contrast, an inelastic is formed of a non-elastomeric
material. Accordingly, by virtue of its composition, inelastic
strands possess no inherent stretch and/or recovery properties.
Hard yarns are examples of inelastic strands. Hard yarns include
natural and/or synthetic spun staple yarns, natural and/or
synthetic continuous filament yarns, and/or combinations thereof By
way of specific example, natural fibers include cellulosic fibers
(e.g., cotton, bamboo) and protein fibers (e.g., wool, silk, and
soybean). Synthetic fibers include polyester fibers (poly(ethylene
terephthalate) fibers and poly(trimethylene terephthalate) fibers),
polycaprolactam fibers, poly(hexamethylene adipamide) fibers,
acrylic fibers, acetate fibers, rayon fibers, nylon fibers and
combinations thereof.
[0037] The upper 105 includes an inelastic strand possessing a
topology that enables it to provide mechanical stretch and recovery
within the knit structure. In an embodiment, the inelastic strand
is a hard yarn texturized to generate stretch within the yarn. In a
preferred embodiment, the inelastic strand is a bicomponent strand
formed of two polymer components, each component possessing
differing properties. The components may be organized in a
sheath-core structure. Alternatively, the components--also called
segments--may be oriented in a side-by-side (bilateral)
relationship, being connected along the length of the strand. As
seen in FIG. 6, the bicomponent strand 400 is a filament including
a first polymer segment 405 and a second polymer segment 410. While
the components may be symmetrical, in the illustrated embodiment,
the strand is eccentric (the polymer components are asymmetrical),
with the first polymer component 405 possessing more volume and/or
mass than the second polymer component 410. It should be
understood, however, that the segments may be generally similar in
dimensions (size, shape, volume, etc.).
[0038] In a further embodiment, the first polymer component of 405
is formed of a polymer possessing a first shrinkage rate (when
exposed to wet or dry heat) and the second polymer component 410 is
formed of a polymer possessing second shrinkage rate. Accordingly,
when the strand 400 is exposed to heat, the polymer components 405,
410 shrink at different rates, generating coils within the strand
400.
[0039] By way of example, the strand 400 is a polyester bicomponent
strand. A polyester bicomponent strand is a continuous filament
having a pair of polyesters connected side-by-side, along the
length of the filament. Specifically, the polyester bicomponent
strand 400 may include a poly(trimethylene terephthalate) and at
least one polymer selected from the group consisting of
poly(ethylene terephthalate), poly(trimethylene terephthalate), and
poly(tetramethylene terephthalate) or a combination thereof. By way
of example, the polyester bicomponent filaments include
poly(ethylene terephthalate) and poly(trimethylene terephthalate)
in a weight ratio of about 30/70 to about 70/30. In a preferred
embodiment, the first polyester component 405 is a 2GT type
polyester polyethylene terephthalate (PET) and the second polyester
component 410 is a 3GT type polyester (e.g., polytrimethylene
terephthalate (PTT)). In an embodiment, the 2GT type polyester
forms about 60 wt % of the strand, while the 3GT type polyester
forms about 40 wt % of the strand. As noted above, the strand 400
may be in the form of, without limitation, a single filament or a
collection of filaments twisted into a yarn.
[0040] Additionally, various co-monomers can be incorporated into
the polyesters of the bicomponent strand 400 in minor amounts,
provided such co-monomers do not have an adverse effect on the
amount of strand coiling. Examples include linear, cyclic, and
branched aliphatic dicarboxylic acids (and their diesters) having
4-12 carbon atoms; aromatic dicarboxylic acids (and their esters)
having 8-12 carbon atoms (for example isophthalic acid,
2,6-naphthalenedicarboxylic acid, and 5-sodium-sulfoisophthalic
acid); and linear, cyclic, and branched aliphatic diols having 3-8
carbon atoms (for example 1,3-propane diol, 1,2-propanediol,
1,4-butanediol, 3-methyl-1,5-pentanediol,
2,2-dimethyl-1,3-propanediol, 2-methyl-1,3-propanediol, and
1,4-cyclohexanediol), isophthalic acid, pentanedioic acid,
5-sodium-sulfoisophthalic acid, hexanedioic acid, 1,3-propane diol,
and 1,4-butanediol are preferred. The polyesters can also contain
additives, such as titanium dioxide.
[0041] With the above configuration, when exposed to heat, the
first polymer (polyester) component 405 shrinks/contracts at a
different rate than the second polymer (polyester) component 410.
This, in turn, produces a regular, helical coil along the length of
the strand 400. In an embodiment, the contraction value of each
polymer segment 405, 410 may range from about 10% to about 80%
(from its original diameter). The strand 400 may possess an
after-heat-set crimp contraction value from about 30% to about
60%.
[0042] The helical coil of the strand 400 generates
non-elastomeric, mechanical stretch and recovery properties within
the strand (e.g., the filament or yarn). That is, the strand
possesses mechanical stretch and recovery without the need to
texturize the strand, which reduces strand durability. A
bicomponent strand, moreover, possesses increased recovery
properties compared to elastic strands at stretch levels of less
than 25%. The recovery power of elastic strands increases with
increasing stretch (e.g., 100% or more). Stated another way, the
further an elastic strand is stretched, the better it recovers. At
low stretch levels, elastic strands generate low recovery power.
This is a disadvantage in footwear uppers, where the amount of
stretch required during use is minimal (e.g., less than 25%).
[0043] The bicomponent strand 400 may possess any dimensions
suitable for its described purpose. By way of example, the
bicomponent strands 400 may be present within the textile as yarn
having a denier of from about 70 denier to about 900 denier (78
dtex to 1000 dtex) and, in particular, from about 100 denier to
about 450 denier.
[0044] The entire upper 105 or sections thereof may be formed
completely of bicomponent strands. In an embodiment, the upper 105
is formed with a combination of bicomponent strands and
non-bicomponent strands such as heat sensitive strands. The
bicomponent strand can be present from about 20% by weight to about
95% by weight (e.g., about 25%--about 75% by weight) based on the
total weight of the textile structure (the entire upper 105 or
sections thereof). Stated another way, the ratio of the bicomponent
strand 400 to other strands within the structure may be about 10:1
to about 1:10 (e.g., 1:1).
[0045] In operation, a bicomponent strand 400 forms a course within
the textile structure. Referring to FIG. 5, the knit structure 500
of the upper includes a plurality of courses 505A, 505B, 505C, and
505D and a plurality of wales 510A, 510B, 510C. Each course 505A,
505B, 505C, and 505D is formed of a strand. In an embodiment, the
knit structure 500 includes a first, bicomponent strand 400 and a
second, non-bicomponent strand 520. In the illustrated embodiment,
courses 505B and 505D are formed of the bicomponent strand 400,
while courses 505A and 505C are formed of the non-bicomponent
strand 520.
[0046] While the illustrated embodiment shows the bicomponent
strand 400 forming alternating courses of the knit structure 500,
it should be understood that the bicomponent strand 400 or the
non-bicomponent strand 520 may form a plurality of successive
courses 505 within the knit structure. For example, the textile
structure 500 includes a plurality of bicomponent strands 400
courses, each bicomponent strand course being spaced a
predetermined number of courses away from an adjacent bicomponent
strand course. In general, the bicomponent strand 400 may form
approximately every second course to approximately every 10th
course. Typically, the spacing remains consistent throughout the
textile structure 100. In other embodiments, the spacing of the
bicomponent strand 400 may be varied to alter the recovery and/or
stretch properties throughout the knit structure 500 (and thus the
textile). By way of specific example, the bicompoent strand 400 may
form every other course of the upper 105 along the toe cage
section, but form every sixth course along the heel section.
[0047] The vamp 225 may further include a microclimate modulation
structure operable to affect movement of heat, air, and/or moisture
(e.g., vapor) within the foot cavity 332. The temperature
modulation structure includes strands selected to possess
predetermined thermal conductivity values positioned at selected
locations within the knit construction of the textile. Referring to
FIG. 6, includes a first construction or portion 605 possessing a
first knit construction and a second construction or portion 610
possessing a second knit construction. The first portion 605 forms
the central area of the vamp 225, being oriented forward the throat
line 250, with its lateral boundaries generally coextensive
therewith, and its forward boundary located proximate the toe cage
230. The second portion 610 partially surrounds the first portion
405, being oriented along its forward, medial, and lateral sides.
Stated another way, the second portion 610 forms the toe cage 230,
the lateral side of the vamp 225, and the medial side of the vamp.
As illustrated, the first portion 605 is integral with the second
portion 610 with a seamless and/or stitchless transition
therebetween. Each portion 605, 610 of the microclimate modulation
structure 400 is independently capable of affecting the movement of
heat, air, and/or moisture within the cavity and/or exhausting it
from the foot cavity 332.
[0048] In an embodiment, the temperature modulation structure 600
includes first, high thermal conductivity strands and second, low
thermal conductivity strands. High conductivity strands are strands
that transfer heat along its length (axis) and/or width (transverse
dimension) at a higher rate than low thermal conductivity strands.
In an embodiment, high thermal conductivity strands are strands
formed (e.g., entirely formed) of material possessing a thermal
conductivity value greater than 0.40 W/m K. By way of example, the
strands may be formed of high density polyethylene (HDPE, 0.45-0.52
@23C) and/or ultra-high molecular weight polyethylene (UWMW-PE,
0.42-0.51 W/m K @23C).
[0049] In a further embodiment, high thermal conductivity strand is
a strand that possessing an axial thermal conductivity of at least
5 W/m K (e.g., at least 10 W/m K or at least 20 W/m K). The high
thermal conductivity strand may be a multifilament fiber such as a
gel-spun fiber. By way of specific example, the high conductivity
strand is a gel-spun, multifilament fiber produced from ultra-high
molecular weight polyethylene (UHMW-PE), which possesses a thermal
conductivity value in the axial direction of 20 W/m K (DYNEEMA,
available from DSM Dyneema, Stanley, N.C.).
[0050] The low thermal conductivity strand, in contrast, transfers
heat along its length (axis) and/or width (transverse dimension) at
a lower rate than that of the high thermal conductivity strand. In
an embodiment, the low thermal conductivity strand is formed (e.g.,
entirely formed) of material possessing a thermal conductivity of
no more than 0.40 W/m K. By way of example, the low conductivity
strand may be formed of low density polyethylene (LDPE, 0.33 W/m K
@23C), nylon (e.g., nylon 6; nylon 6,6; or nylon 12) (0.23-0.28 W/m
K @23.degree. C.), polyester (0.15-0.24 W/m K @23.degree. C.),
and/or polypropylene (0.1-0.22 W/m K @23C).
[0051] In another embodiment, the low thermal conductivity strand
possesses an axial thermal conductivity (as measured along its
axis) that is less than the axial conductivity of the high
conductivity strands. By way of example, the low thermal
conductivity strands possess an axial thermal conductivity value of
less than 5 W/m K when high thermal conductivity strand possesses a
thermal conductivity of greater than 5 W/m K; of less than 10 W/m K
when high conductivity strand possesses a thermal conductivity of
at least 10 W/m K; and/or less than 20 W/m K when high conductivity
strand possesses a thermal conductivity of greater than 20 W/m K.
Exemplary low thermal conductivity strands include strands formed
of polyester staple fibers (axial thermal conductivity: 1.18 W/m
K); polyester filament strands (axial thermal conductivity: 1.26
W/m K); nylon fiber strands (axial thermal conductivity: 1.43 W/m
K); polypropylene fiber strands (axial thermal conductivity: 1.24
W/m K); cotton strands (axial thermal conductivity: 2.88 W/m K);
wool strands (axial thermal conductivity: 0.48 W/m K); silk strands
(axial thermal conductivity: 1.49 W/m K); rayon strands (axial
thermal conductivity: 1.41-1.89 W/m K); and aramid strands (axial
thermal conductivity: 3.05-4.74 W/m K), as well as combinations
thereof.
[0052] The sole structure 110 comprises a durable, wear-resistant
component configured to provide cushioning as the shoe 100 impacts
the ground. In certain embodiments, the sole structure 110 may
include a midsole and an outsole. In additional embodiments, the
sole structure 110 can further include an insole that is disposed
between the midsole and the upper 105 when the shoe 100 is
assembled. In other embodiments, the sole structure 110 may be a
unitary and/or one-piece structure. As can be seen, e.g., in the
exploded view of FIG. 1, the sole structure 110 includes an upper
facing side 125 and an opposing, ground-facing side 130. The upper
facing side 125 may include a generally planar surface and a curved
rim or wall that defines the sole perimeter for contacting the
bottom surface 135 of the upper 105. The ground-facing side 130 of
the sole structure 110 can also define a generally planar surface
and can further be textured and/or include ground-engaging or
traction elements (e.g., as part of the outsole of the sole
structure) to enhance traction of the shoe 100 on different types
of terrains and depending upon a particular purpose in which the
shoe is to be implemented. The ground-facing side 130 of the sole
structure 110 can also include one or more recesses formed therein,
such as indentations or grooves extending in a lengthwise direction
of the sole structure 110 and/or transverse the lengthwise
direction of the sole structure, where the recesses can provide a
number of enhanced properties for the sole structure (e.g.,
flexure/pivotal bending along grooves to enhance flexibility of the
sole structure during use).
[0053] The sole structure 110 may be formed of a single material or
may be formed of a plurality of materials. In example embodiments
in which the sole structure includes a midsole and an outsole, the
midsole may be formed of one or more materials including, without
limitation, ethylene vinyl acetate (EVA), an EVA blended with one
or more of an EVA modifier, a polyolefin block copolymer, and a
triblock copolymer, and a polyether block amide. The outsole may be
formed of one or more materials including, without limitation,
elastomers (e.g., thermoplastic polyurethane), siloxanes, natural
rubber, and synthetic rubber.
[0054] With the above-described configuration, an upper formed of a
knit textile may be provided with stretch and recovery properties
without the use of strands/yarns formed of elastomeric material
such as rubber or elastane. In embodiments, no strands possessing
elastomeric stretch are present within the textile structure (i.e.,
the entire footwear upper and/or an entire section of the footwear
upper). Eliminating elastomeric strands improves the overall weight
of the upper since it is no longer necessary to plait (braid)
elastomeric strands onto an existing strand forming the course.
Instead, the bicomponent strand is the only strand forming the
course.
[0055] Additionally, elastomeric strands capture water.
Accordingly, an upper containing no elastomeric strands provides an
upper that dries quicker than conventional uppers including
elastomeric strands. Referring to FIG. 7, a comparison of textile
structures lacking elastomeric strands to textile structures
including elastomeric yarns is provided. Specifically, a textile
including spun polyester and a bicomponent polyester (about 25%
bicomponent fiber) was compared to a first textile structure
(Conventional #1) including 95% cotton fiber and 5% elastane fiber
(plaited onto the cotton) and a second textile structure
(Conventional #2) including 60% cotton, 40% polyester, and 5%
elastane (plaited onto the cotton and/or polyester). As shown, the
knit structure including bicomponent strands was not only lighter
in weight, but dried quicker than the conventional knit
structures.
[0056] A method of forming an article of footwear is disclosed with
reference to FIG. 8. As shown, the process 800 includes (Step 805)
knitting a footwear structure including courses and wales by
inserting a bicomponent strand into selected courses within the
structure. As explained above, the bicomponent strand includes a
first component polymer integrally formed with a second component
polymer. At step 810, a non-bicomponent strand is inserted into
selected courses within the footwear structure. As explained above,
a non-bicomponent strand includes the inelastic, heat sensitive,
heat insensitive strands discussed above, as well as the low and/or
high thermal conductivity strands. At Step 815, upon formation of
the knitted footwear structure, the footwear structure is exposed
to wet or dry heat. The temperature should be sufficient to
activate the bicomponent strand, generating coiling within the
strand. In addition, when thermally sensitive strands are present,
the temperature applied should be sufficient to initiate softening
(when a softening strand), melting (when a fusible strand), or
setting (when a thermosetting strand). After heating, at Step 820,
the resulting footwear structure (e.g., the upper) may be coupled
to the upper via adhesives, stitching, etc.
[0057] While the invention has been described in detail and with
reference to specific embodiments thereof, it will be apparent to
one skilled in the art that various changes and modifications can
be made therein without departing from the spirit and scope
thereof. For example, while most of the example embodiments
depicted in the figures show an article of footwear (shoe)
configured for a right foot, it is noted that the same or similar
features can also be provided for an article of footwear (shoe)
configured for a left foot (where such features of the left footed
shoe are reflection or "mirror image" symmetrical in relation to
the right footed shoe).
[0058] While not being elastomeric, the bicomponent strand 400
still possesses good stretch and recovery. While a recoverable
stretch of 25% is suggested above, other recoverable stretch ranges
may be utilized. For example, a recoverable stretch of at least
75%, preferably at least 100%, and more preferably up to 150% or
more (per, e.g., ASTM D6720-07)). In an embodiment, the bicomponent
strand recovers rapidly and substantially to its original length
when stretched to one and half times its original length (150%) and
released.
[0059] The footwear upper 105 or a portion of the footwear upper
(e.g., one of the sections 210, 215, 220, 225, 230, 240, 300) may
include a course of bicomponent strand 400. As noted above, the
footwear upper 105 or a portion of the footwear upper (e.g., one of
the sections 210, 215, 220, 225, 230, 240, 300) may be formed
primarily (e.g., >50%), substantially (e.g., >90%), or
completely (100%) of bicomponent strands (with any remainder being
non-bicomponent strands).
[0060] Within the knit structure, various stitches may be used to
provide different sections 210, 215, 220, 225, 230, 240, 300 of the
upper 105 with different properties. For example, a first area may
be formed of a first stitch configuration, and a second area may be
formed of a second stitch configuration that is different from the
first stitch configuration to impart varying textures, structures,
patterning, and/or other characteristics to the upper member.
[0061] Stitching may be utilized to connect sections of the upper
together. In addition, a thermoplastic film may be utilized to
reinforce seams, replace stitching, and/or prevent fraying. For
example, seam tape available from Bemis Associates, Inc. (Shirley,
Mass.) may be utilized. Instead of an instep cover 240, the upper
105 may include a conventional tongue including a longitudinally
extending member free on its lateral and medial sides.
[0062] It is to be understood that terms such as "top", "bottom",
"front", "rear", "side", "height", "length", "width", "upper",
"lower", "interior", "exterior", "inner", "outer", and the like as
may be used herein, merely describe points of reference and do not
limit the present invention to any particular orientation or
configuration.
[0063] Thus, it is intended that the present invention covers the
modifications and variations of this invention provided they come
within the scope of the appended claims and their equivalents.
* * * * *